425 Series 23:1 Ratio, 4-1/4" Air Motor 1.8 GPM (6.9 LPM) max flow 600 Series 46:1 Ratio, 6” Air Motor 1.8 GPM (6.9 LPM) max flow 800 Series 13:1 Ratio, 8" Air Motor 12.2 GPM (46.3 LPM) max flow